1. Field of the Invention
The present invention relates to an optical disk reproducing apparatus that plays back information recorded on an optical disk, and in particular, to a technique of processing a user operation of skip up/skip down with respect to an optical disk, in which user operation control information for controlling whether or not the user operation is practicable is additionally recorded, while the optical disk is played back.
2. Description of the Related Art
In an optical disk for a DVD (digital versatile disk) video that is recently used, a disk manufacturer records, on the disk, information that restricts a user operation (UOP) with respect to functions, such as search, fast forward, or quick return, so as to restrict the user operation.
FIG. 5 is a view illustrating user functions, where user operations for realizing the user functions can be controlled by recording restriction information on an optical disk for a DVD video. In FIG. 5, Yes indicates that a user operation with respect to a corresponding user function can be controlled by a user operation bit (UOP bit) in corresponding title • search pointer • table (TT_SRPT), program • chain information (PGCI), or video • object • unit (VOBU) and No indicates that the user operation with respect to the corresponding user function cannot be controlled thereby.
In an optical disk reproducing apparatus that plays back the optical disk, the optical disk is played back so as to read out user operation control information indicating a permission or a restriction of the user operation as shown in FIG. 5, that is, user operation control (VOBU_UOP_CTL) information of video • object • unit (VOBU) included in navigation pack (NV_PCK) of control information recorded on the optical disk, and then when a user performs a user operation which is restricted, warning indicating that the user operation is restricted is given on the optical disk by using, for example, mark display and a user function corresponding to the user operation is not performed.